Roll forming of metal products can be traced back as far as 600 BC in various cultures across Europe and the Far East. Early processes were crude and simple, employing hand-operated equipment forming metals such as tin, lead and copper into an array of shapes used for covering the exterior of buildings as roofing or trim work.
Roll forming has become an invaluable part of building construction
Roll forming of metal roofing and other products has continued to evolve since the late 1700s as it was used more and more as long-lasting fireproof covering for building construction in that period. Since then, the process has undergone many changes and improvements as have the types and quality of metals formed. Coiled metal rolls or strips of flat metal could be fed into the equipment individually or continuously depending on the type of product made and speed that they were running.
Roll forming was instrumental to producing long runs of a single-shape product. The shapes could include holes and notches in the metal fed to the roll former. They were then cut to length by a specially designed shear at the exit end of the equipment that matched the product shape or a flat blade shear at the entry end of the machine. The exit end shear cut to a specific shape according to the profile being run is the most desirable method of cutting a roll formed product and provides the most job control.
The roll former itself has also undergone improvements over the years in order to produce a more consistent product faster and without damage. Marring of the metal surface has also been significantly reduced, which is a major concern of the design community today. Early forming was done with solid steel rollers which were susceptible to pitting and damage. They’ve been replaced with chrome-plated rollers that provide a long-lasting polished surface to prevent damage to the high-tech paint finishes used in the market now.
The forming process itself has also undergone some significant changes. Early motorized forming equipment drove the material through the machine and formed at the same time. This tended to induce a certain amount of stress in the metal as it was being formed which led to a greater chance of producing a twisted or oil-canned finished product. Today many rollformers employ a separate set of neoprene-drive rollers within the machine to pull the metal through the forming rollers and produce a clean, straight, consistent product. These neoprene rollers also help pull it through in a straight line and prevent the material from “walking” across the forming stations.
Roll forming equipment design allows a variety of metals and thicknesses to be formed on the same machine with very little adjustment, yet maintains the shape and quality to meet the required product standards. This process also provides the advantage of full-length products (up to sizes that can be shipped if the roll former is fixed inside a plant) as opposed to products restricted to the length of standard metal forming brakes, typically between 8 feet and 12 feet long.
Of course, there are exceptions with brakes as long as 30 feet in some instances. Roll forming common shape in metal roofing, gutter, wall panel, etc., where the project will require thousands of feet of a particular product is much more economical than forming individual pieces on a brake.
Today’s advanced roll forming equipment includes options to further speed production and increase efficiency, such as computer-controlled batch counters that can be set to run continuous batches of material into specific lengths and piece counts automatically when the equipment is fed by a coil of metal. Roll formers can also be fitted with a hot melt sealant applicator to apply a bead of sealant to the panel shape when required as the panel is roll formed. This too works in conjunction with the computer-controlled batch counter. Roll formers can be set up for in-plant stationary production with an electric motor or can be built with a gas engine for remote field use in areas where a stable electric supply is not available.
Roll forming has become an invaluable part of building construction today, providing a wide range of products to many different trades. New uses for roll formed products are emerging every day and the availability of roll forming equipment has grown and advanced to meet that challenge.
Joe Tripod is chief operating officer at Englert Inc., Perth Amboy, N.J. To learn more, visit www.englertinc.com or call 1-800-ENGLERT.
